Node-red-contrib-devicefinder NPM

node-red-contrib-devicefinder

node-red-contrib-devicefinder is a module for Node-RED for interacting with USB connected X-keys devices using SuperFlyTV's nodejs library.

Dependencies

Apart from Node-RED itself, the node-red-contrib-devicefinder module depends on xkeys (2.2.1) and usb-detection (4.10.0).

The provided example flow additionally depends on node-red-dashboard (2.30.0).

Installation

For normal use in the Node-RED web interface, the node-red-contrib-devicefinder node is most conveniently installed using the Palette Manager. In the Manage palette widget, select the Install tab and search for devicefinder which should soon list node-red-contrib-devicefinder. Select the associated install button to complete the installation. A new devicefinder node should now be available in the function section the flow editor's palette side-bar.

If the installation initially fails with messages like:

 [err] ERR! usb-detection@4.10.0 install: `prebuild-install || node-gyp rebuild`
 [err] npm ERR! Exit status 1
 [err] npm ERR!
 [err] npm ERR!
 [err]  Failed at the usb-detection@4.10.0 install script.

then run the following commands in a terminal:

sudo apt install -y build-essential
sudo apt install libudev-dev

Now try again to install node-red-contrib-devicefinder as above.

Of course the code itself may be also downloaded by cloning the repo or by running npm install node-red-contrib-devicefinder

Usage

An example flow to demonstrate typical use of the new devicefinder node can be found in the examples directory. To use it requires that the node-red-dashboard has also been installed using the Palette Manager. The example flow may then be loaded using the Node-RED main menu's Import item; in the window that pops up, select the Examples tab and then navigate to flows/node-red-contrib-devicefinder and select ShowDevices and press the Import button. This should open a new Show Devices tab in the flow editor.

When deployed, connected X-keys devices are listed on your Node-RED's dashboard page (typically the same url as the flow editor page but adding /ui to the url e.g. http://localhost:1880/ui (or, more generally, http://\<ip-address>:1880/ui). As devices are plugged into or removed from the host machine, their device name should appear in, and disappear from, the upper DEVICE LIST section of the dashboard display. Selecting any one of the listed devices produces information about that device in the middle DEVICE INFO section. If the Read data button in pressed and a device has been selected, the button text will change to Reading ..., after which any physical manipulation of the selected device (button press, jog, shuttle, joystick or T-bar movement) should produce corresponding data in the bottom data section. Pressing the Clear button clears the data section.

Double clicking a device, as well as selecting it, will blink the selected device's physical LED for a few seconds, thus confirming two way communication with the device.

A selected device may be soft rebooted using the Reboot button i.e. the device will restart as if it were physicially removed and then reattached to the host machine. In so doing, it will momentarily disappear from the dashboard's device list and reappear shortly afterward (within seconds). If no device is currently selected, the Reboot button has no effect.

Upgrading

When a new version of node-red-contrib-devicefinder is released, it will be visible in the Palette Manager after searching for devicefinder in the Nodes tab. Pressing the update to x.x.x button there will raise a notification warning of the need to restart Node-RED after the update occurs. Restart Node-RED by running node-red-restart in a terminal window. If using the example flow that is part of a node-red-contrib-devicefinder release, it's a good idea to also update that too as it will typically have new functionality to showcase features of the update. Before updating, remove any flow tabs containing the old example flow and create a new flow with very little in it e.g. just an Inject node. Now deploy this dummy flow to ensure that NodeRED doesn't try to deploy an old devicefinder example flow after the compulsory restart. After restart, load the updated example flow with the same procedure outlined in the Usage section above. After pressing the _Import button a warning about already existing nodes will appear; press the Import copy button to complete the update. Then press Node-RED's Deploy button to restart the new flow.

Issues

On Linux, including Raspberry Pi, if no connected devices are detected, it's likely that there is a permissions issue which, as mentioned at SuperFlyTV's xkeys project site, can be fixed by installing the appropriate configuration file as quoted here:

Save the following to /etc/udev/rules.d/50-xkeys.rules and reload the rules with sudo udevadm control --reload-rules && sudo udevadm trigger
SUBSYSTEM=="input", GROUP="input", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="05f3", MODE:="0666", GROUP="plugdev"
KERNEL=="hidraw*", ATTRS{idVendor}=="05f3", MODE="0666", GROUP="plugdev"